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Old 06-16-2019, 08:47 PM   #1701
F-Line to Dudley
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Re: Regional Rail (including North-South Rail Link)

Quote:
Originally Posted by Riverside View Post
Good points, I hadn't considered the impact that the uncertainty of whether seats would be filled would have.

Makes sense about the Springfield corridor, but hasn't the Shore Line East arrangement been much more long-standing?
The SLE arrangement is legacy cruft dating to 2003 when 4 New London SLE trains had to be cut back to Old Saybrook in order to add 4 AMTK Regionals to the schedule, because of limitations on the number of allowable bridge openings of the Connecticut River Bridge. The cross-tix program was expanded somewhat in 2008, but is asterisked to only certain trains.

They're able to execute it because Amtrak is the contracted operator for SLE (much like they were for the T from 1988-2004), and so all onboard conductors are Amtrak employees. They have since found other means to increase service by begging and pleading for more individual bridge openings, so the cross-honoring is on tenuous ground long-term. A new Connecticut River Bridge was in final stages of design towards the end of the Obama Administration, but has seen no action on federal funding shares since so is not close to starting. The new basclule span would operate fast enough to dramatically expand the New London schedule and end the need to truncate runs at Old Saybrook. Most likely that's when they'll pull the plug on the cross-tix arrangement with Amtrak, since it is first and foremost a kludge to get bodies past that bridge traffic restriction and not any sort of 'natural' perk of the corridor.
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Old 06-18-2019, 05:28 AM   #1702
F-Line to Dudley
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Re: Regional Rail (including North-South Rail Link)

FCMB item:

https://cdn.mbta.com/sites/default/f...accessible.pdf

T has committed to an accelerated deployment of cab signals (Automatic Train Control, or ATC) on the entire northside commuter rail, to match their usage on the southside. Cab signals work with the train-detecting track circuits that are already there to provide speed and stop enforcement. Positive Train Control (PTC) of the Amtrak variety that the T is deploying--called "ACSES"--then works on top of the cab signal layer providing the added safety features and traffic management flex that PTC offers.

Cab signals were previously banned from the northside because of legacy cruft from the big 1976 Boston & Maine line sale to the T, in which B&M (and successor Pan Am) reserved the perpetual rights to continue operating their freight fleets without that equipment. The PTC mandate grants the T a temporary exemption to install a variant of ACSES PTC that can run without cabs, but it's a cumbersome arrangement that will leave a lot of padding flab in the schedules because the PTC overlay has to default to a higher state of caution. It's also not certain the FRA will agree to extending the northside's exemption (though they had indicated they were willing), possibly leaving the T in a lurch if they didn't have a design plan for the new signal system in place. Last year the FCMB quietly granted a design contract for the system, without explaining anything about next steps for installation. Now apparently they're feeling confident enough about clearing the hurdles to go full speed ahead.

Pan Am has recently purchased dozens of cheap-beater secondhand GE locomotives from CSX that already do have cab signal units, and is either retiring scores of its ancient locos or banishing them to the woods of Maine. While they were still resisting dropping the cabs ban as little as a year ago, apparently they've reached enough critical mass on fleet turnover (and gotten enough MassDOT payola) to let it fall.

p. 5 of the presentation bullets out the main advantages of the system in layman's terms. The "shorter headways" bullet is an absolutely necessary one for implementing RER, so that's good news. Cabs also help simplify the amount of radio bandwidth the northside's PTC would otherwise have to suck up in overcompensation, and it allows for retirement of all intermediate wayside signals to trim the amount of field hardware. The cabbed lines down south (right now all but Franklin, Needham, and inner half of Worcester...which are each having it installed in time for next year's PTC deadline) only have lighted signals at junctions and interlockings (powered switches like crossovers), while the northside will have them every 1-2 miles to mark a block. It also unites north and south signaling under the same rulebook, cutting out a lot of training overhead for employees and opening up the potential for uniting northside and southside dispatch under one roof instead of being forever-separate. Unified signaling is a very big deal if you envision NSRL not only being built, but also working well in practice.

On the timetable, the Western and Eastern routes lag the other two because the double-track portions of the inner Western from Wyoming Hill-Reading and Rockport Branch Beverly-Gloucester still use a very obsolete form of Automatic Block Signalling (ABS) with no direct train detection via track circuits...with signals fed through ancient telephone wire. All of that needs to be ripped out and replaced for fiber and track circuits in order to support the new system.

Since this change has reverberations throughout the northside, see if NNEPRA starts making noises soon about needing this on the Downeaster to pack and speed the schedule through NH and ME. There are some significant toilet clogs outside of MBTA territory where this could potentially help.
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